Pattern-based mapping for storage space management

1. A method for storage space management, the method comprising: activating a logical volume group; reading a mapping formula from physical volumes in the logical volume group; and using a mapping formula to determine a target physical extent in at least one of the physical volumes for a received request; wherein the mapping formula is based on a number of extents in a logical volume, a physical volume, and a starting offset of a physical extent in the physical volume.

2. The method of claim 1 , wherein the mapping formula maps a logical volume to a physical volume.

3. The method of claim 2 , wherein the mapping formula maps logical extents in the logical volume to physical extents in the physical volume.

4. The method of claim 1 , further comprising: storing the mapping formula in a host memory.

5. The method of claim 4 , further comprising: using the mapping formula to determine the target physical extent for the request.

6. The method of claim 1 , further comprising: storing the mapping formula into the physical extents.

7. The method of claim 1 , wherein the mapping formula indicates at least one of: a number of extents in a logical volume, at least one physical volume, and a starting offset of a physical extent in the physical volume.

8. The method of claim 1 , wherein the mapping formula permits an increase in a data structure size to be stored in meta-data regions in the physical volumes.

9. An apparatus for storage space management, the apparatus comprising: a volume manager configured to activate a logical volume group, read a mapping formula that translates from physical volumes in the logical volume group, and use the mapping formula to determine a target physical extent in at least one of the physical volumes for a received request; wherein the mapping formula is based on a number of extents in a logical volume, a physical volume, and a starting offset of a physical extent in the physical volume.

10. The apparatus of claim 9 , wherein the mapping formula maps a logical volume to a physical volume.

11. The apparatus of claim 10 , wherein the mapping formula maps logical extents in the logical volume to physical extents in the physical volume.

12. The apparatus of claim 9 , wherein the volume manager is configured to store the mapping formula in a host memory.

13. The apparatus of claim 12 , wherein the volume manager is configured to use the mapping formula to determine the target physical extent for the request.

14. The apparatus of claim 9 , wherein the volume manager is configured to store the mapping formula into the physical extents.

15. The apparatus of claim 9 , wherein a mapping formula indicates at least one selected from the group consisting of: a number of extents in a logical volume, at least one physical volume, and a starting offset of a physical extent in the physical volume.

16. The apparatus of claim 9 , wherein the mapping formula permits an increase in a data structure size to be stored in meta-data regions in the physical volumes.

17. An article of manufacture, comprising: a non-transitory machine-readable medium having stored thereon instructions to: activate a logical volume group; read a mapping formula from physical volumes in the logical volume group; and use the mapping formula to determine a target physical extent in at least one of the physical volumes for a received request; wherein the mapping formula is based on a number of extents in a logical volume, a physical volume, and a starting offset of a physical extent in the physical volume.